Apparatus for applying labels to objects having a helically grooved gluine roller

ABSTRACT

An apparatus for applying labels to bottles or the like comprises at least one moveable gluing palette 7 which coacts with a rotary gluing roller 1 so as to be coated with glue, and which thereafter transfers the glue to a label 17 which is transported by the palette from a label magazine 11 to a gripper 12 which grips the glue-coated label and presses it onto a bottle 15. The outer cylindrical surface of the gluing roller is provided with helical grooves 2 which are kept filled with glue, and the outer layer 10 of each gluing palette is slightly elastic so that when the palette is urged into contact with the ridges 3 extending between the grooves on the gluing roller, parts of the outer layer will be pressed partially into the grooves so as to come into contact with the glue present in the grooves.

BACKGROUND OF THE INVENTION

The present invention relates to an apparatus for applying labels toobjects, such as bottles or the like, comprising at least one moveablegluing palette which is intended to coact with a rotary gluing roller soas to be coated with glue and thereafter to transfer glue to a labelwhich is transported by the palette from a label magazine to a gripperwhich is intended to grip the glue-coated label and press the label ontothe object concerned.

Devices of the aforedescribed kind are used, among other things, toapply labels to bottles in breweries, soft-drink bottling plants andlike plants, which require the labelling devices to operate at highspeed. The majority of these devices include a rubber gluing roller,aluminium gluing palettes and an adjustable glue scraper which isoperative in determining the thickness of the glue on the gluing roller.

These known devices must be produced with extreme accuracy and anysubsequent adjustments to the devices in operation must be effected veryprecisely, since, for instance, the gluing palettes may only partiallypenetrate the glue layer on the gluing roller without making contactwith the outer surface of the roller itself, since such contact wouldforce the glue layer carried by the roller out onto the edges of thepalette. This would cause glue to splash or squirt onto the palettesurroundings, and would also result in glue fastening to the front sideof the labels, causing the labels to be drawn off the bottles. Looselabels which fasten to the gluing roller are difficult to remove and mayresult in damage to the roller, particularly when using foil labels,since such labels can cause wear on the roller when fastening betweenthe glue scraper and the roller. A certain amount of wear can also becaused when the operator scrapes away labels that have fastened to thegluing roller with the aid of a sharp tool.

Another serious drawback with the known apparatus is that labels whichfasten between the glue scraper and the gluing roller are liable toprevent the application of a fresh layer of glue on the roller, meaningthat subsequent labels will not be completely coated with glue and thatthese glue-depleted labels will not stick to the very fast movingbottles. This may make it necessary to remove from the production line avery large number of bottles which lack labels.

Another factor is that the clearance between the gluing palettes and thegluing roller must not be excessive, since an excessive clearance willprevent the palettes from coming into contact with the glue, with theresult that the labels will not be adequately coated.

The known apparatus are thus very sensitive to non-roundness of thegluing roller and also to wear on said roller, and require precise andplay-free journalling of the roller.

DE-A1-3 131 164 describes a gluing machine or apparatus in which thegluing palettes are permitted to make contact with the gluing roller,wherein both the palettes and the roller are provided with mutuallyintersecting grooves. This arrangement, however, suffers severaldrawbacks, since, among other things, the ridges located between thegrooves become coated with intersecting glue beads which are pressed outonto the edges of the palettes as the ridges come into contact with oneanother and splash down onto the surroundings and also result in gluefastening to the front side of the label.

SUMMARY OF THE INVENTION

The prime object of the present invention is to provide labellingapparatus with which the aforesaid drawbacks of known techniques areeliminated, among other things.

The invention is based on the realization that this object are achievedwhen the gluing roller and the gluing palette can be constructed so thatthe palettes are able to contact the outer surface of the roller withoutcausing glue to splash down onto the surroundings. In this way, theextremely high tolerance requirements of known apparatus, with which thepalettes are only permitted to penetrate partially into the actual gluelayer, are avoided.

Accordingly, an apparatus in accordance with this invention is primarilycharacterized in that the cylindrical outer surface of the gluing rolleris provided with grooves which are intended to be kept filled with glue;and in that at least the outer layer of each gluing palette is somewhatelastic so that when the palette is pressed into contact with the ridgeslocated between the grooves on the gluing roller, parts of said outerlayer will be pressed slightly into said grooves so as to come intocontact with the glue present therein.

By using, in accordance with the invention, a grooved gluing roller incombination with gluing palettes having an elastic outer layer, thepalettes, although they make contact with the surface of the roller,willnot force out glue which penetrates up to the side edges of thepalettes, while ensuring effective glue transfer at the same time.

It is preferred that the apparatus will include at least one nozzle bymeans of which glue is delivered to the roller, and that the grooves inthe surface of the roller are held filled with glue with the aid of ascraper which coacts with the roller and which lies against the ridgesextending between said grooves, so as to keep the ridges free from glue.The gluing roller is conveniently vertically oriented, and the gluenozzle is arranged at the upper end of the roller. The grooves providedin the gluing roller are preferably helical grooves which extendadjacent one another. Among other things, this provides a self-cleaningroller, since any labels which might stick to the roller will be"screwed" towards one end of the roller by the action of the gluescraper.

According to one preferred embodiment, the rotational speed of thegluing roller and the working cycle of the gluing palettes is chosen sothat the ridges between the roller grooves will coact with at leastpartially different parts of respective palettes after each precedingcontact occasion. This rotational speed of the gluing roller and thepitch of the grooves are preferably so selected that theridge-contacting surfaces of the palettes are shifted slightly downwardson the palette between mutually sequential contacts of said palettesurfaces with said ridges.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail with reference to anexemplifying embodiment thereof illustrated in the accompanyingdrawings.

FIG. 1 is a side view of an inventive labelling apparatus.

FIG. 2 is a view of the apparatus shown in FIG. 1 from above.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the drawings, the reference numeral 1 identifies a verticallyoriented, rotary gluing roller whose outer cylindrical surface is madeof a hard material and provided with helical grooves 2, which areseparated by intermediate ridges 3, conveniently flat ridges. Thegrooves are held filled with glue which is delivered to the grooves bymeans of an upper nozzle 4 and is distributed in the grooves and scrapedfrom the ridges by means of a vertically oriented glue scraper 5 whichresiliently abuts the ridges 3 separating the grooves 2 on the outersurface of the roller 1. This ensures that the ridges 3 will be keptfree from glue.

The reference numeral 6 identifies a carousel, which in the illustratedcase is provided with three glue palettes 7, each of which is mountedfor limited pivotal rotation about an associated pivot shaft 8. Thewhole of the carousel 6 rotates about a centre shaft 9. The gluingpalettes may be made of a solid elastic material or of metal and coatedwith an elastic outer layer 10, see FIG. 1, having a flatlabel-contacting surface.

The reference numeral 11 identifies a magazine for labels 17, while thereference numeral 12 identifies a rotary gripper provided withfoam-rubber pads 13 having label-gripping devices. The reference numeral14 identifies a carousel for bottles 15 which shall be labelled withlabels taken from the magazine 11. The entire apparatus can be supportedon a stand 16 which includes a gearbox having appropriate output shaftsfor the various rotational movements.

When the aforedescribed arrangement is in operation, each gluing palette7 will pivot in relation to the gluing roller 1, in a conventionalmanner as the carousel 6 rotates, so that a layer of glue is applied torespective palettes 7 as they pass the roller. The palette then performsa corresponding movement as it passes the label magazine 11, wherein thefirst of the labels 17 in the magazine 11, in which the rear sides ofthe labels face forwards, fastens temporarily to the palette 7. When thelabel arrives at the gripping cylinder 12, as the carousel 6 rotates,the gripping devices in coaction with a foam-rubber pad 13 take thelabel from the palette 7 and, as the cylinder 12 rotates, press theglue-coated surface of the label against the appropriate bottle 15 onthe bottle carousel 14, in a conventional manner. Transfer of the labelfrom the palette 7 to the gripping cylinder 12 and pressing of the labelonto the bottle 15 may also take place in a conventional manner.

In accordance with the present invention, the aforedescribed apparatusis primarily characterized in that the gluing roller is provided withgrooves 2 and that the gluing palettes 7 have an elastic outer layer 10.As before mentioned, this enables the gluing palettes 7 to make contactwith the gluing roller and to perform a rolling movement in relationthereto, without glue being forced out onto the edges of the palettesand while ensuring that glue will be effectively transferred as a resultof the aforesaid partial penetration of the elastic outer layer on thegluing palettes into the glue-filled grooves on the roller.

This greatly reduces the necessary manufacturing and adjustmenttolerances, which, among other things, also reduces both manufacturingcosts and operating costs and provides an apparatus which is much morereliable in operation and which ensures that a good result will beachieved.

The grooves 2 on the gluing roller 1 will preferably have the form ofhelical grooves so that, among other things, a label or some otherobject which might fasten to the gluing roller will be automatically"screwed" downwards along the roller by the action of the scraper 5 asit moves along the ridges. The roller thus becomes self-cleaning, whichis highly advantageous. Scrap and surplus glue can be collected at thebottom end of the roller.

In order to avoid the ridges 3 located between the grooves 2 on theroller 1 from becoming coated with glue, the gluing palettes 7 willpreferably coact with essentially the same surface on the gluing rolleron each rolling occasion. In order, however, to avoid uneven wear on theouter surface of the gluing palettes, it is preferred that the rollingsurface is shifted slightly between sequential contact of a gluingpalette with the roller. To this end, the rotational speed of the gluingroller is adapted in relation to the working cycle of the gluingpalettes, so that the roller will not rotate through a completerevolution or through several complete revolutions between each paletterolling movement. However, it is necessary that the peripheral speeds ofthe roller and the palette essentially coincide.

The rotational speed of the gluing roller and the pitch of the gluegrooves are conveniently chosen so that the palette-contacting surfacesof the ridges will engage the palette successively at locations whichare slightly displaced downwards in relation to preceding engaginglocations. The distance through which the contact surfaces are displacedbetween each contact occasion may be on the order of some hundredths ofa millimeter.

The grooves may be relatively shallow, on the order of some tenths of amillimeter, depending on the desired thickness of the glue layer and onthe quality of the glue used. The grooves may have a width of somemillimeters, depending on the size of the label surface required to becoated with glue. By allowing the pitch of the grooves to vary along thegluing roller, the amount of glue can be varied between different partsof a label or between labels that are located at different heights. Inaddition to helical grooves, horizontal, circumferential grooves mayalso be used for instance, and the pitch between these grooves may bevaried as desired.

The novel features of the present invention can be applied withdifferent types of labelling apparatus, for instance irrespective of thenumber of palettes used, the type of label magazine used, and theconstruction of the gripping devices mounted on the gripper.Furthermore, the palette carousel may be arranged to rotate in onedirection or to pivot backwards and forwards between two positions.

I claim:
 1. An apparatus for labelling objects, comprising at least onemoveable gluing palette (7) adapted to coact with a rotary gluing roller(1) so as to be coated with glue and thereafter to transfer the glue toa label (17) received onto the glue on the palette from a label magazine(11) and then transported to a gripper (12) intended to grip theglue-coated label and to press the glue-coated label onto an object(15), wherein an outer cylindrical surface of the gluing roller isprovided with mutually adjacent grooves (2) adapted to be kept filledwith the glue; and at least an outer layer (10) of each said gluingpalettes are slightly elastic so that when the palette is individuallyurged into contact with ridges (3) extending between the grooves on thegluing roller (1), parts of said outer layer will be pressed partiallyinto the grooves so as to come into contact with the glue present insaid grooves, and further comprising means for implementing aself-cleaning roller function, said implementing means comprising theroller grooves being helically configured, and a scraper (5) coactingwith the roller and lying against the ridges extending between thegrooves to keep the ridges free from the glue such that the scrapercooperates with the helical grooves to screw advance any label or otherforeign object adhering to the gluing roller to one end of the roller.2. An apparatus according to claim 1, further comprising at least onenozzle (4) which functions to deliver the glue to the roller, whereinthe gluing roller is vertically oriented, and the glue nozzle is mountedat an upper end of the roller.
 3. An apparatus according to claim 1,wherein a rotational speed of the gluing roller and a working cycle ofthe gluing palettes (7) are chosen so that the ridges between the rollergrooves will coact with at least partially different regions ofrespective gluing palettes (7) on each successive contact with thepalette.
 4. An apparatus according to claim 3, wherein the rotationalspeed of the gluing roller and a pitch of the grooves are chosen so thatsurfaces of the ridges which come into contact with the respectivegluing palettes will be displaced slightly downwards on the palettebetween each successive contact of the ridges with said palette.
 5. Anapparatus according to claim 4, wherein the pitch of the grooves variesbetween different parts of the roller.